Criminal investigations are often carried out wholly or in part on the Internet. This is particularly true of investigations of crimes that are themselves committed entirely or partly over the Internet, for example crimes involving exploitation of children, gambling, pornography, and various kinds of fraud and larceny. Even if the actual crime is committed using other instrumentalities, evidence of the crime often exists in electronic form, and sometimes only in electronic form.
Successful prosecution of any crime requires reliable, accurate evidence that meets various legal standards for admissibility. Gathering such evidence over the Internet presents special problems in that subject matter on the Internet is transient and easily changed. There has been a need for way to efficiently collect evidence over the Internet together with the time and date when the evidence was collected, and to preserve that evidence in a form that is provably authentic in the context of a criminal prosecution.